According to the Canadian Cancer Society, prostate cancer is the most common cancer among men in this country (other than non-melanoma skin cancers).Illustration by Photo illustration by The Globe and Mail. Sources: iStock; Pexels (man)
Ask a Doctor is new series of physician-authored columns offering insights and advice on common health topics. It is not a substitute for seeking medical care.
‘Wait, you’re not doing the … finger check?’
This is one of the most frequent questions I hear from my male patients during regular checkups. When I explain that evolving science suggests the digital rectal exam is not necessarily the best way to screen for prostate cancer, I see a look of surprise – followed by one of joyous relief.
Screening for prostate cancer is important. According to the Canadian Cancer Society, prostate cancer is the most common cancer among men in this country (other than non-melanoma skin cancers), and the third leading cause of cancer-related deaths.
However, how we approach screening for prostate cancer is informed by the latest understanding we have of the disease and the tools available to us for screening. Not everyone benefits from the same approach.
Who’s at risk?
Understanding who is most at risk is the first step for informed decision-making.
Men older than 50, and those with a family history of prostate cancer, are at a higher risk of developing the disease.
In addition, Black men have a higher incidence of prostate cancer than men of other ethnic backgrounds.
Factors such as diet and weight may also play a role.
Who should get screened – and how?
“Screening” means checking for a potential disease in someone who has not been diagnosed with it and has no symptoms of the illness. So we have to be mindful that screening tools don’t cause more harm than the benefits they may bring.
Here is how I explain the two tests used for prostate cancer screening to my patients.
Digital rectal exam (DRE)
Traditionally, the DRE has been a standard component of prostate cancer screening. However, current recommendations suggest that the DRE may not be necessary for all patients. The simple reason is that a doctor’s finger can only feel about one-third of the surface of the prostate. If cancers are growing on the other sides, or growing within the prostate itself, the physician cannot feel it. As such, the test is not really useful for patients who do not have symptoms. This is why I have stopped doing the DRE as a routine part of my screening practice.
In patients who do have symptoms suggesting a prostate problem (see below), we still do a DRE as part of the assessment.
Prostate-specific antigen (PSA) test
The PSA test measures the amount of prostate-specific antigen – a protein produced by the prostate – in the blood. Elevated PSA levels can indicate prostate cancer, but they may also result from other conditions (such as bladder infections or recent urological procedures).
The Canadian Cancer Society recommends that average-risk individuals consider screening with the PSA test starting at age 50. It also advises that high-risk individuals, including Black men and those with a family history of prostate cancer, consider testing from age 45.
However, the Canadian Task Force on Preventive Health Care advises against using the PSA test for screening. Its review of nonindustry funded, primary-care literature suggests that the potential harms of the PSA test – such as false positive test results and unnecessary treatments – outweigh the potential benefits.
In guidelines published in 2014, the task force says: “For men under 55 years and 70 years and older, there is no evidence that screening with the PSA test reduces mortality whereas there is evidence of harms. For men aged 55 to 69 years, there is inconsistent evidence of a small potential benefit of screening, and evidence of harms.”
Given such contradictory advice, what should men do?
I suggest a thorough and nuanced conversation about PSA screening with your family doctor, taking into account your medical and family history. It’s essential to discuss the limitations and potential benefits and harms of PSA testing in order to make an informed decision.
Benefits include early detection, which can potentially lead to more effective treatment. Limitations and potential harms include false-positive test results, which can lead to anxiety, plus unnecessary further testing and subsequent possible complications (for example, infection and erectile dysfunction). PSA testing can also result in overdiagnosis. Research suggests that up to half of prostate cancers detected through screening are overdiagnosed, meaning these cancers are slow-growing and would not have caused symptoms or death during the patient’s lifetime.
Symptoms to monitor
It is important to know the symptoms of prostate cancer because when they do present, it would be prudent to use the screening tools that we have available.
Early-stage prostate cancer often presents without noticeable symptoms. But as the disease progresses, symptoms may include: difficulty urinating or a weak urine stream; frequent urination, especially at night; anything else unusual about urination or ejaculation (blood, pain et cetera).
While these symptoms can also be associated with other conditions, such as benign prostatic hyperplasia or infections, it is crucial to consult with your doctor for an accurate diagnosis.
Preventive measures
Although there is no guaranteed method to prevent prostate cancer, certain lifestyle choices may reduce your risk.
Eating a balanced diet rich in fruits, vegetables and whole grains while limiting red meat and high fat dairy is advised. Engaging in regular physical activity and maintaining a healthy weight can also reduce cancer risk, as can avoiding tobacco and limiting alcohol intake.
Dr. Yan Yu is a family physician in Alberta and the Northwest Territories. He practises in numerous clinical settings such as community-based family medicine clinics, long-term care homes, hospitals and rural emergency rooms. He is also the founder and director of Joyce Health, an online child and adolescent psychiatry clinic. His clinical interests include child and adolescent psychiatry and providing care to rural, remote and Indigenous communities. In his spare time, he creates medical education videos on YouTube.
